Enhanced antimicrobial and biocompatible properties of polylactic acid nanocomposites reinforced with agave sisalana cellulose nanofibres

Abstract

The growing demand for sustainable and biodegradable materials in biomedical applications motivates this study on biodegradable poly (lactic acid) (PLA) nanocomposites reinforced with cellulose nanofibres (CNFs) derived from Agave sisalana. The nanocomposites were fabricated via solvent casting. SEM analysis confirmed uniform dispersion of CNFs and enhanced interfacial bonding with the PLA matrix. XRD results indicated an increase in the crystalline regions of PLA due to CNF incorporation, contributing to improved mechanical strength and thermal stability, which are critical for biomedical implants. Thermal degradation studies showed a 19°C increase in degradation temperature compared to plain PLA, indicating enhanced heat resistance. Mechanical testing revealed a 48.4 % increase in tensile strength and a 66.1% increase in Young’s modulus relative to plain PLA, demonstrating the reinforcing effectiveness of CNFs. Chemical degradation tests showed accelerated hydrolytic and environmental degradation of the nanocomposites compared to plain PLA, beneficial for controlled biodegradation. Additionally, antimicrobial activity improved with increasing CNF content against common pathogens. Hemolytic and MTT assays confirmed good biocompatibility at 3 wt% CNF loading, highlighting the potential of these nanocomposites for safe biomedical applications.